OpenMarine

Full Version: IMU orientation
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Hi,
Is there any rules for orientation of the IMU? I’m as confused as my compass! I have a MPU9250 hooked up, and I have followed the calibration procedures and everything seems fine. However my heading only show variation of a few degrees on a full 360 turn. Flipping the IMU over on a specific side makes the compass come to live, but of cause disrupts the pitch and roll reading. Calibrating leveraging again to align pitch and roll brings me back to the broken compass response. I have tried with both a mpu9255 and two different  mpu9250 - same result.

Currently the Pypilot is running with the tilted IMU showing wrong pitch and roll data, but I get a decent performance - but I must be doing something wrong?

Attached is screenshoots of the web client and the client calibration matrix.
https://share.icloud.com/photos/0I6-g_h4...LrbYLkAM9w

It is an issue for me to run the Pypilot_calibration since I’m running on a headless pi with virtual VNC, and the calibration won’t start due to pywavefont or pyglet...
The calibration is supposed to still run without pywavefront, it just wont' render the boat...

In any case, it sounds like you have not managed to calibrate the compass. It is also possible that you have bad sensors.. There are a lot of bad mpu9255 out there, and these will not work in all orientations.

I am not able to see your screenshot icloud error.

Also, did you manage to calibrate the accelerometers? This fixes most of the "bad" mpu that didn't work in all orientations. 90% of mpu9255 don't need to calibrate accelerometers.